1. Field of the Invention
The present invention relates to a method of fabricating at least a honeycomb body or, in particular, to a drying process and a drying system.
2. Description of the Related Art
In fabricating at least a honeycomb body of ceramic, at least an argillaceous honeycomb body is extrusion molded dried and baked. A method of drying at least a honeycomb body is known, as described in Japanese Unexamined Patent Publication No. 63-166745, and uses a high frequency current generated by applying a voltage between the electrodes arranged above and below a honeycomb body. This method is intended to heat the interior and the exterior of the honeycomb body uniformly thereby to prevent such defects as cracking and wrinkling which may be caused by a shrinkage difference attributable to the difference in the drying rate.
The drying method described above is effectively applicable to a honeycomb body having a cell wall thickness of 0.30 to 0.15 mm and an outer peripheral skin thickness of 0.3 to 1.0 mm generally used in the prior art as a catalyst carrier of an exhaust gas purification system of an automobile. In a thin-wall honeycomb body having a cell wall thickness of not more than 0.125 mm and an outer peripheral skin thickness of not more than 0.5 mm which has recently been developed to meet the need of an improved exhaust gas purification performance, however, the cell wall and the outer peripheral skin have a strength lower than those of the prior art. For this thin-wall honeycomb body, the conventional method of using a high frequency current cannot fully prevent defects in the outer peripheral portion.